Warning of a "looming catastrophe," the UN humanitarian organization said on Thursday that the de facto blockade of aid access to the Tigray region in northern Ethiopia is pushing millions of people to the brink of famine.

The United Nations Agency for the Coordination of Humanitarian Affairs, Ocha, has called on all warring parties 10 months ago in Tigray to allow the transfer of assistance to the region.

5.2 million people, or 90 per cent of the population, were in dire need of humanitarian assistance, and 400,000 of them were already facing conditions of famine.

Referring to the removal of other obstacles to access, the Agency called in particular on the Ethiopian Government to allow aid supplies and individuals into and within the country by "lifting bureaucratic obstacles."

Adding that 172 trucks were stranded in the town of Semera near Tigray, the Office for the Coordination of Humanitarian Affairs said that there was only one route to Tigray that could currently be used by the United Nations and relief groups, and logistical and bureaucratic obstacles made passage "extremely difficult."

At a press conference, Ethiopian Prime Minister Belen Seyom's spokeswoman rebuffed allegations that the Ethiopian Government was blocking aid, confirming that trucks were "en route" to Tigray, adding that the number of checkpoints on the road referred to by the United Nations had fallen to three out of seven.

It should be noted that war broke out in the Tigray mountainous region last November between Ethiopian forces and the Tigray People's Liberation Front, which controls the area. The conflict has killed thousands, displaced hundreds of thousands more and caused a massive humanitarian crisis.